HelioClim-3 Archives

What is HC3?

The satellite-derived solar radiation database HC3) uses the Heliosat-2 method, which estimates a "cloud index", based on the analysis of the 15 minute Meteosat Second Generation (MSG) satellite images in the visible band. Our most advanced HC3 version 5 applies then this "cloud index" to a "clearsky model" computed from a precise atmosphere description in terms of water vapor, aerosols and ozone, name McClear (~3 hours and ~40 km resolution, worldwide).

In addition, we enhance the native spatial resolution of MSG (which is about 5 km at 45° of latitude), by computing inside a MSG pixel the irradiation variation due to the altitude and to the shadow of the horizon for a specific point. The relief used to compute the shadowing is obtained from the SRTM digital surface model (DSM), with a spatial resolution of ~100m.

All annual subscriptions include an unlimited access to the Web interface, and up to 200 automatic requests per day (or per month depending on your subscription). A price is applied per request beyond 200.

"HC" stands for HelioClim, then just add the time step and the plane orientation (default: horizontal). Eg.: "HCdayIncl" means "HelioClim3 daily irradiation values over an inclined plane".

The annual subscription to a HC3 service offers an unlimited access to this product via the SoDa website during the twelve months following the opening of the account. The subscription to a product offers also access to products with a larger temporal step. For instance, the subscription to the HC15 service also allows to access to the products HCHour, HCDay, HCWeek and HCMonth. Moreover, the subscription of a product on an inclined (or normal) plane enables the access to the equivalent product on the horizontal plane. For instance, if you purchase HC15Incl, you will also be granted the possibility to assess to the services previously listed, as well as: HCmonthIncl, HCdayIncl and HChourIncl.